This invention relates to an automatic control system for receiving a weather alert broadcast, and more particularly a radio system which operates automatically for receiving and broadcasting a weather alert from weather stations.
Weather alerts are broadcasted by weather stations in various regions covering different parts of the country and the world. Weather radios are receivers for listening to such weather alert broadcasts in weather bands operated in the frequency modulated (FM) signal. Heretofore, weather alerts radio receivers operate to receive first a weather alert alarm signal, and after hearing the alarm signal, it is necessary for the user to switch the receiver manually to the broadcasting mode of the weather station in order to listen to the actual weather alert broadcast. Such systems are, for example, shown in U.S. Pat. No. 4,633,515 to Uber et al, and U.S. Pat. No. 4,392,248 to Eckels et al. Since the weather radio user may not be located immediately near to the receiver to switch it over to the broadcasting mode, or that the user may be preoccupied with other tasks and is unable to operate the change over switch, the operation of such system is therefore awkward and inconvenient to carry out. Furthermore, it is necessary for the listener to change the tuning of the receiver manually to a different channel so as to receive a broadcast from each different weather station.
A weather band may be incorporated in a multi-band radio receiver which may be operated to receive broadcasts from any of the AM, FM, or weather band selectively. However, the drawback in such multi-band radio receiver is that each broadcast band operates independently such that the weather alert alarm signal can not be received when the radio is operating in either the AM or FM band. The radio must be set at the weather band at all times in order to receive the weather alert alarm signal. The ambient noise in such weather broadcast band is quite high during the absence of any weather alert alarm such that it is annoying to the user. For this reason, users tend to turn off the weather band entirely, resulting in the danger of not receiving any weather alert alarm signal.
It is a principal object of the present invention to provide a control system which operates automatically for controlling the weather band radio for receiving and broadcasting the weather alert announcement.
It is another object of the present invention to provide a weather alert radio receiver having selective automatic mode and manual mode which operate to receive and to broadcast a weather alert announcement from various weather stations.
It is yet another object of the present invention to provide a control system for a multi-band AM/FM and weather band radio receiver which operates automatically for receiving and broadcasting weather alert announcements regardless of any selected band it is normally operating, and it will also automatically return to the originally selected AM or FM band at the termination of the weather alert broadcast.
The multi-band radio receiver of the present invention includes AM and FM bands for receiving AM and FM broadcasts and a weather band for receiving weather warning alert and weather broadcast from a plurality of weather stations to provide automatically an audible output of the weather warning alert and the weather broadcast regardless of whether or not the receiver is normally operating in the AM or FM band or the weather band. The broadcasts are announced by an audio means of the receiver. The receiver includes an automatic control comprises a frequency stepping circuit means operative continuously for scanning and tuning the receiver to search the plurality of weather stations for the weather alert and weather broadcast transmitted by a carrier frequency signal. A detecting means is adapted to segregate the weather warning alert and weather broadcast from the carrier frequency signal. A squelch circuit means is connected to the detecting means and in combination therewith adapted to determine the presence of the weather warning alert and the weather broadcast. A filter means is connected to the detecting means and is adapted to provide a trigger output signal in response to the weather warning alert. An alert audio oscillator means is connected to the filter means and is adapted to generate a unique alert signal when a weather warning alert is received. A switching comparator means coupled to the detecting means and is adapted to provide an actuation output signal when the weather warning alert and weather broadcast are present. A switching means is connected to the switching comparator means and the alert audio oscillator means and is operative by the actuation output signal for conveying the unique alert signal and weather broadcast to the audio means. An auto lock circuit means is coupled to the frequency stepping circuit means and the detecting means and is operative to lock the frequency stepping circuit means at one of the plurality of weather stations which is presently announcing the weather warning alert and the weather broadcast. An AM/FM output switch means is connected to the squelch circuit means and is adapted to disconnect the AM or FM broadcast from the audio means while the unique alert signal and weather broadcast is being announced by the audio means, and it will re-connect the selected AM or FM broadcast to the audio means at the termination of the announcement of the unique alert signal and the weather broadcast.